measuring the pepsin activity. dependence of the velocity of the reaction on the actual pH

Question 1

the function of pepsin?

Answer 1

cleaves proteins producing peptides and peptides into amino acids

Question 2

which molecules are soluble in TCA (trichloroacetic acid)?

Answer 2

oligopeptides and amino acids

Question 3

how can you determine the activity of pepsin

Answer 3

by measuring the amount of tyrosine and tryptophan

folin’s reagent gives a positive result with tyrosine and tryptophan

Question 4

materials needed for this experiment

Answer 4

 Diluted blood plasma (50x)
 Pepsin solution (dissolved in physiological saline;
4g/1)
 HCl (0.2 mol/l)
 Na2CO3 (0.1 mol/l)
 Trichloroacetic acid (0.6 mol/l)
 Spectrophotometer
 Water bath at 37 °C
 Filter paper
 Plastic funnel